基于能量和链路状态的AODV路由请求转发机制研究

按需距离矢量路由算法(AODV)为移动无线自组织网络(Manet)提供了高效的、扩展性能良好的路由解决方案.然而AODV在选择路径时仅以最短路径和最快响应作为度量准则,并未考虑节点能量、负栽以及链路状态等因素,导致得到的路径并非为最优且节点能量消耗不均衡,降低了网络生存时间.在传统AODV算法基础上,提出了一个改进的路由算法,该算法在路由选择时充分考虑了节点的能量、负载以及节点间的链路状态,可以有效提高网络性能并延长网络生存时间.在NS2平台上的仿真实验结果也显示,所提算法在路由负荷、时延、分组传递率以及节能方面均优于传统AODV算法.     

蓝牙分散网的多径不相交的路由算法

蓝牙的分散网是一种特殊的自组网．由于蓝牙设备的连接和通信的特性，传统自组网的路由协议不适于蓝牙网络．针对这个问题，提出了一种多径不相交(MPD)的路由算法．仿真结果表明，采用多条路径并行发送数据，提高了数据的投递率，减少了端到端之间的传输延迟，从而有效地减少了网络拥塞；避免了由于路由崩溃，造成系统瘫痪．     

On reactive routing protocols in ZigBee wireless sensor networks

ZigBee is the primary standard solution for wireless sensor networks, implementing the Ad hoc On‐Demand Distance Vector (AODV) protocol in the network layer and supported by the standard IEEE 802.15.4. This study is focused on mesh topologies and the critical problems encountered when AODV is executed in conjunction with the Carrier Sense Multiple Access with Collision Avoidance protocol. These problems are mainly related to the packet overhead required to carry out route creation. To perform preliminary experiments to be able to implement AODV in a real network, a new metric is proposed herein. This metric uses fuzzy logic to help in the decision‐making process. The objective of the fuzzy routine is to determine, during the route‐discovery process, the best node to forward request/reply packets, with the aim of reducing packet overhead and energy consumption. Moreover, minor changes are also added to the discovery procedure of AODV to improve the performance of the route‐creation process. This intelligent version of AODV has provided promising experimental results, greatly reducing the number of packets required, with the consequent energy saving while selecting the best nodes to be part of the routes.     

Ad hoc网络节点不相交多路径距离矢量路由协议

AMR算法是Ad hoc网络计算节点不相交最大路径集合的累积多路径路由机制。针对节点不相交多路径源路由协议MNVP及SMNVP存在的问题,整合按需距离矢量路由AODV和AMR算法,提出了节点不相交多路径距离矢量路由协议MDVRo MDVR协议建立的路径信息分布在网络节点中,可缩短路由分组长度以及减轻路由发现源节点建立路由的负担;可防止攻击者通过墓改路由消息中的路径信息攻陷协议。     

移动自组网中基于节能的AODV路由协议改进

在AODV路由算法的基础上,综合考虑节点剩余能量和跳数,提出了一种新的节能路由策略。该策略同时对数据包和路由控制包进行功率控制,改进了Hello机制。仿真结果显示该策略显著地提高了节能效果,延长了网络的生存时间。     

Balancing the power consumption speed in flat and hierarchical WSN

A combination of a cluster tree routing protocol and an Ad hoc on demand vector (AODV) routing protocol is used in the latest ZigBee standard wireless sensor networks (WSNs) technology. However, the AODV routing protocol has no means by which to take into consideration the power consumption of the nodes during the routing process. Therefore, a new approach is proposed in this paper to balance the power consumption speed and to distribute the responsibilities of routing among fiat wireless sensor nodes and the three levels of hierarchical wireless sensor nodes. These three levels are based on the three types of devices, which are used in the ZigBee standard: the coordinator, the touters, and the end devices. In this paper, we have compared the original AODV routing protocol with our extension approach for the distribution of power consumption. Based on the simulation results, our new approach has achieved better performance in terms of increasing the lifetime of the fiat wireless sensor network, the personal area network (PAN)coordinator, the touters, and the whole network of the hierarchical wireless sensor network. Additionally, it has better performance in terms of distributing the power consumption among the key nodes of the wireless sensor network.     

双向路径重选的自组网负载均衡路由协议

基于跨层负载感知和双向路径重选的自纽网负载均衡路由协议（CLBLR）在路由发现阶段和路由维护阶段，将整个路径中各节点MAC层的总平均估计时延和路径总业务流负载结合起来，共同作为路由选择和路由调整的重要依据，通过双向路径重选方法实现最优路径选择和网络业务流的均衡分布和均衡传输．协议通过禁止中间节点对路由请求进行应答和阻止不必要的路由请求分组，经由重负载中间节点转发，以保证路由发现时能够利用最新负载信息，并避免了节点在重负载情况下成为新建路由的中间节点，使协议具有一定的拥塞控制功能，以间接的方式实现了请求接纳控制．上述措施使分组传输路由很好地避免了拥塞节点，减少了网络瓶颈对网络性能的影响．仿真表明，CLBLR在分组丢失率、平均端到端时延和路由附加开销等方面具有良好性能，其优良的分布式控制特征能适应自组网的动态环境．     

MANET路由子层微移动管理

在采用无线自组网按需平面距离矢量(AODV)路由协议的移动自组网(MANET)网关设计中,针对MANET节点的微移动特性,提出应用于MANET路由子层的微移动管理策略,并在AODV路由协议中进行实现。在NS2平台上的仿真结果表明,采用微移动管理策略的MANET网关可有效降低MANET网络访问Internet的时延,并能减少MANET内控制报文的开销。     

按需式ad hoc移动网络路由协议的研究进展

Ad hoc移动网络是一种完全由移动主机构成的网络，网络拓扑易变，带宽，能源有限是ad hoc移动网络的主要特点，针对这些特点，目前设计的ad hoc路由协议大多采用按需查找方式，该文介绍了这方面研究的最新进展，对几种典型的按需路由协议进行了说明，分析和综合比较，文中分析了目前协议存在的一些问题并提出了相应的改进方法，最后指出了下一步研究方向。     

一种基于跨层功率控制的Ad hoc网络路由算法*

在无线Ad Hoc网络路由协议中引入功率控制不但可以降低网络能量消耗,同时还能改善网络的吞吐量、投递率等性能,已成为当前Ad Hoc网络的一个研究热点.本文提出了一种基于跨层功率控制的按需路由算法CPC-AODV(Cross-layer Power Control Ad hoc On-demand Distance Vector).算法按需建立多个不同功率级的路由,节点选择到目的节点最小功率级的路由来传递分组,并对网络层的数据分组、路由分组和MAC层控制帧的传输采用不同功率控制策略来降低能量消耗.仿真结果表明:算法有利于降低通信能量开销,延长网络寿命,提高网络投递率及改善网络时延.     

节点度估计和静态博弈转发策略的Ad Hoc网络路由协议

针对Ad Hoc网络路由发现过程中广播路由请求分组导致的广播风暴问题，提出了一种基于节点度估计和静态博弈转发策略的Ad Hoc网络路由协议NGRP.NGRP考虑边界影响，采用分段函数的思想将网络场景分为中心、边和角区域，分别估算网络中节点在不同区域的节点度，避免了周期性广播Hello消息获取节点度导致的开销；NGRP路由请求分组的转发采用静态博弈转发策略，利用节点度估算参与转发路由请求分组的节点数量，将转发和不转发作为策略集合，设计效益函数，通过纳什均衡获得节点转发路由请求分组的转发概率，从而减少了路由请求分组广播过程中产生的大量的冗余、竞争和冲突，提高了路由发现过程中路由请求分组的广播效率.运用NS-2对协议的性能进行大量的仿真，结果表明：NGRP的分组投递率、路由开销、MAC层路由开销和吞吐率这4项指标明显优于AODV+FDG，AODV with Hello和AODV without Hello协议.     

Modelling and verifying the AODV routing protocol

This paper presents a formal specification of the Ad hoc On-demand Distance Vector (AODV) routing protocol using AWN (Algebra for Wireless Networks), a recent process algebra which has been tailored for the modelling of mobile ad hoc networks and wireless mesh network protocols. Our formalisation models the exact details of the core functionality of AODV, such as route discovery, route maintenance and error handling. We demonstrate how AWN can be used to reason about critical protocol properties by providing detailed proofs of loop freedom and route correctness.     

Adjusted probabilistic route discovery in mobile ad hoc networks

Conventional on-demand route discovery methods in mobile ad hoc networks (MANET) employ simple flooding method, where a mobile node blindly rebroadcasts received route request (RREQ) packets until a route to a particular destination is established. This can potentially lead to high channel contention, causing redundant retransmissions and thus excessive packet collisions in the network. This paper proposed two new probabilistic methods that can significantly reduce the number of RREQ packets transmitted during route discovery operation. Our simulation analysis reveals that equipping AODV with an appropriate probabilistic route discovery method can result in significant performance improvements in terms of routing overhead, MAC collisions and end-to-end delay while still achieving a good throughput when compared with the traditional AODV.     

AODV协议的选播QoS扩展研究与仿真

针对移动自组网(Ad hoc)的特点和AODV协议的可扩展性,提出了一种适合Ad hoc的选播QoS路由协议AQAODV,该协议在考虑选播路由特点的基础上,扩展AODV以支持QoS需求,并采用局部路由恢复技术,在动态变化的Ad hoc网中实现了一种高效的选播QoS路由.仿真结果表明,AQAODV协议在带宽、时延和平均路由开销等方面较AODV协议具有明显的性能优势.     

基于局部邻居节点和链路权值的改进AODV路由协议

在节点高速移动的Ad Hoc网络环境中,广播风暴对网络性能的影响尤为重要,且网络拓扑结构的频繁变化极易导致路由中断.传统的AODV路由协议在路由发现阶段直接使用广播转发RREQ（路由请求分组）机制,容易导致广播风暴降低网络性能;同时,协议选择跳数最少的路径作为路由,没有考虑到节点的快速移动导致路由频繁失效,因此无法适应节点高速移动的网络环境.针对上面存在的问题,提出一种对AODV进行改进的协议.该协议在路由发起过程中,基于局部邻居节点数量计算动态转发概率;选择路由时,利用跨层思想,结合网络节点移动速度提出链路权值,依据链路权值选择路由路径.NS2仿真结果表明：该改进协议提高了数据包的投递率,缩短了端到端的传输时延,能够更好地适应节点高速移动的网络环境.     

高能量节点驱动的按需距离矢量路由协议

无线自组织网络中的按需距离矢量路由协议(AODV)没有考虑到能量消耗的均衡性和网络生命期的问题。针对AODV的这一缺点,提出了一种高能量节点驱动的AODV协议(HN-AODV)。此协议将高能量节点驱动的策略应用于按需路由发现过程,尽量选择能量较高的节点来承担转发任务,以此来平衡网络能耗。仿真结果显示,HN-AODV在基本不降低数据传输性能的前提下,显著提高了网络生命周期。这种高能量节点驱动的方案同样可以运用在其它类似的反应式路由协议中。     

自组网中一种基于跨层负载感知的按需负载均衡路由

本文提出了一种新的基于跨层负载感知的自组网负载均衡路由协议（CLLOR）。CLLOR在路由发现阶段和路由维护阶段将整个路径中各节点MAC层的总平均估计时延和路径总业务流负载结合起来共同作为路由选择和路由调整的重要依据,以实现网络业务流的均衡分布和均衡传输。协议通过禁止中间节点对路由请求进行应答和阻止不必要的路由请求分组经由重负载的中间节点转发,以保证路由发现时能够利用最新的负载信息,并避免了节点在重负载情况下成为新建路由的中间节点,使得协议具有一定的拥塞控制功能,以间接的方式实现了请求接纳控制。通过上述措施,可以很好地避免网络中出现拥塞节点,减少了网络瓶颈对网络性能的影响。仿真表明,CLLOR在分组丢失率、平均端到端时延和路由附加开销等方面具有良好的性能,其优良的分布式控制特征能适应自组网的动态环境。     

A location routing protocol based on smart antennas for ad hoc networks

Ad hoc networks are a type of mobile networks that function without any fixed infrastructure. One of the weaknesses of ad hoc networks is that route between a source and a destination is likely to break during communication. Location-based routing algorithms are promising in reducing routing overhead in ad hoc networks. Existing location-based routing algorithms employ the Global Positioning System (GPS) as their location information provider, and synchronize information network-wide. Nonetheless, these protocols have some limitations because the use of GPS is not realistic in certain circumstances. Since smart antenna is able to infer direction and ranging information between pairs of ad hoc node, the obtained local position information can be used to improve routing mechanism. This work proposes a novel Location-Enhanced On-Demand (LEOD) routing protocol which is based on smart antenna technique. The LEOD protocol utilizes local position instead of global position to discover routes and make routing decision for the ad hoc network. Theoretical computation and simulation results show that data packet loss rate decreased significantly compared to other methods well-documented in the literature. In addition, this protocol reduces the network control overheads and the power consumption. It also improves network average throughput.     

一个两步蓝牙散射网形成算法TBSF

蓝牙是一门新兴的低功耗、低成本短距离无线技术，它使便携设备能方便快捷地形成短距离无线网，同时为构建成本低廉的移动自组网带来了新的选择方案．提出一个异步的、完全分布式蓝牙散射网构造算法——TBSF，首先由所有蓝牙节点生成一系列独立匹克网，然后互连匹克网成为散射网．基于节点邻居个数选择主或桥节点，通过一个节点角色转换图确定桥节点充当的角色．任意两个相邻匹克网之间通过惟一的连接路由互连，最终形成一个连通的散射网，主和桥节点构成散射网的一个连通支配集．仿真实验表明，TBSF算法创建散射网具有较好特性．     

Efficient dynamic-power AODV routing protocol based on node density

Mobile Ad Hoc Networks (MANET) allows versatile communication between host devices moving around in a state of flux. These networks have no fixed infrastructure thus making the routing of packets a continuous challenge to be optimally delivered under varying criteria such as when the number of nodes within an area increases the scope for interference between nodes which also increases significantly. Additionally, MANETs have low stability in areas with fast moving nodes which leads to their reduced longevity. This paper proposes a method by adapting the standard Ad hoc On-Demand Distance Vector (AODV) protocol to dynamically adjust transmission power usage, which is titled Dynamic Power-Ad hoc On-Demand Distance Vector (DP-AODV). This method uses the dependence of a transmission range on density to achieve this improvement. The results demonstrate that as density increases, DP-AODV shows decrease in delay than AODV and offering better performance for highly populated networks exceeding 200 nodes. The simulation results show that DP-AODV increase network throughput whilst reducing the node interference in a dense region, as well as it enhances the overall network performance with respect to the increased packet delivery fraction, reducing the control overheads and jitter, enhancing overall throughput, reducing interferences and finally, shortening end-to-end delay in medium to high density conditions.